"We must all bear the burden," Gallant said, addressing what has long been a divisive political issue in a country with mandatory military service for most citizens.

Since Israel was founded in 1948, Jewish men who study the Torah full-time in a yeshiva are granted an annual deferment from military service until the age of 26, at which point they become exempt.

But since the war in Gaza erupted after Hamas's October 7 attack, a decades-old debate around these exemptions has gained a new urgency.

On Wednesday, Gallant called for an end to the exemptions, saying he would back legislation to this effect if it is endorsed by centrist ministers in the ruling coalition of Prime Minister Benjamin Netanyahu.

"An immediate need arises for the extension of military service for our active soldiers and the prolongation of reserve duty for reservists," Gallant told journalists on Wednesday evening.

"It is not a matter of choice. We must stand firm in defending our homeland.

"It is possible and important to reach an agreed framework for a draft (law), even for a growing part of the ultra-Orthodox community which is already contributing to the civilian effort," he said.

Gallant's comments have raised new concerns of a political crisis in Israel at a time when it is fighting Hamas militants in Gaza.

The exemptions given to ultra-Orthodox yeshiva students have ballooned as the community's population has grown over the decades.

This has fuelled resentment among Israeli society at large.

Israel called up more than 300,000 military reservists as it launched its costly war against Hamas in the aftermath of the October 7 attack on southern Israel, which resulted in the deaths of around 1,160 people, mostly civilians, according to an AFP tally of official Israeli figures.

Gallant called on Netanyahu "to lead a shared process with all coalition parties and reach necessary agreements on the issue of a draft law".

Gallant said the law needs backing from all parties.

"Without agreement from all parts of the coalition, the defence establishment that I head will not submit the law," he said.

His remarks were welcomed by cabinet minister Benny Gantz, a former defence minister himself who joined Netanyahu's emergency coalition after the war began.

An impasse over the issue could threaten Netanyahu's coalition of ultra-Orthodox and religious nationalist parties.

Gallant's remarks drew criticism from Amichai Eliyahu, Israel's heritage minister and a member of the Jewish Power faction in Netanyahu's government.

"There is no possibility whatsoever to draft this community forcibly," Eliyahu told Army Radio.

"At the moment I prefer unity of the people of Israel and the country to the government collapsing" over this issue, he said.